The invention refers to a collating and stitching machine with an endless conveyor conveying the sheets to be gathered towards a stitching station with at least one stitching head and with at least two rotating sheet delivery drums, which are arranged above and along the endless conveyor in spaced relationship.
Collators are known in the art, whereby an endless conveyor is used to form a collating chain. On the side of the chain or above the chain are arranged a number of rotating sheet delivery drums which take from vertically or horizontally stacked sheet staples signatures and sheets, respectively, open the sheets and let them slide onto the collating chain. Since the axis of the known rotating sheet delivery drums extend parallel to the conveying direction of the chain, there is a sudden variation of direction when the sheets are laid down onto the collating chain. The reason for the sudden variation in direction is because the conveying direction of the collating chain is perpendicular to the centrifugal force applied to the sheets by said rotating sheet delivery drums and perpendicular with respect to the gravitational force of the sheets. Normally, the individual sheet is taken from the associated feeder magazine, gripped by grippers and is accelerated by a first sheet delivery drum, which moves the sheet by use of the grippers against a stop, at which stop the grippers set the sheet free. The abutment at the stop causes a complete deceleration of the movement applied by the drum. Subsequent drums arranged beneath the first drum take the sheet, move it downwardly and open it. When opening grippers are used, a post or premargin is necessary; with the use of suction fingers, a closed head is necessary with the sheet. The drums arranged after the first drum let the sheet slide down onto the collating chain which takes the sheet by means of cams and varies its direction of movement by 90.degree.. The multiple variations of the direction of movement necessary for the entire operation and the acceleration and decelerations associated therewith limits the possibility of increasing the capacity of the prior art collating chain. Any increase in speed beyond this limit creates great suceptability to trouble.
The collators with the sheet delivery drums arranged on the side of the chain require increased space. Independently of the arrangement of the sheet delivery drums, either on the side of the collating chain or above the chain, the known collators have the disadvantage that the trimmer normally located behind the collator has to be arranged perpendicular to the collating chain. Moreover, the prior art collators cannot be combined with inserting machines to form an integral system, rather, the inserting machine is normally arranged behind the trimmer leading to a further reorientation of the product flow by 90.degree. due to the following reasons: through the cutting machine the product, e.g. a periodical, is transported with the closed back or fold leading the direction of movement. In the normal inserting machines the periodical, however, has to be arranged in such a manner that the closed back lies parallel to the direction of movement of the inserting machine so that the periodical can be opened by a knife moving into the periodical. Then, the insert is moved into the opened periodical while the direction of movement of the periodical and the insert are at a 90.degree. angle. With the prior art arrangements used up to now, self-addressing of the printed periodicals is required immediately after the printing and production process, the periodical has, again, to be reoriented by 90.degree., since for self-addressing, the periodical has to be transported again with the closed back or fold leading the direction of movement.